Note: Descriptions are shown in the official language in which they were submitted.
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PORTABLE DEVICE FOR DESTROYING NEEDLES
This invention relates to improved apparatus for safely and
efficiently destroying used hypodermic needles.
BACKGROUND OF THE INVENTION
Used hypodermic needles often contain residues of potentially
dangerous materials, such as blood carrying ~IV, hepatitis B or other
infectious ~lice~eç~. Because the sharp tips ofthe needles may prick the skin
of persons a~ pLillg to dispose of them, many devices are available for
destroying the needles. Some of such devices utilize incineration aw~dllls
that generate electric culle1lL~ that destroy the needle, crushing ~a~dlLIs thatgrinds and crushes the needle and the syringe housing, or apparatus using a
combination of both incineration and crushing.
For example, U.S. Patent No. 5,076,178 to Kohl, et al.
discloses a needle incineration device. Insertion of the needle to be
destroyed pushes a carriage unit that couples to an electrical power source for
sending a high voltage electric current through the carriage unit and into the
needle. However, "carriage movement is limited to insure that an operator
does not attempt to incinerate the entire length of an extraordinarily long
needle in a single operation and thereby exceed power capacity limits." Like
the device disclosed by Kohl, et al., other devices such as the one described
- in U.S. Patent No. 4,628,169 to Ch'ing-L'ung exist that require the user
carefully to feed the needle into the a~pal~us to ensure destruction of the
needle. Similarly, U.S. Patent No. 4,877,934 to Spinello disclose a device
that is "self-powered" through an optional rechargeable battery and that also
requires the user to feed progressively shorter lengths of a needle into the
device in order for incinerating ~;ull~,nl~ to destroy the needle. Thus, using
the Spinello or Ch'ing-L'ung devices, it is likely that a hurried or careless
user could destroy only part of the needle, leaving a dangerous "stub."
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Such careful feeding is further complicated by the fact that
needles come in a variety of sizes. If too large a needle is being destroyed~
the destruction device may not develop suff1cient current to destroy the
needle completely or destruction may take a long time. Similarly, if too
small a needle is being destroyed, the electrodes of an incinerator-type
destruction device may be too far apart to allow the needle to close the circuitbet~veen the electrodes. Furthermore, constant use of the device may wear
down the electrodes, further se~ g them, or may leave the electrodes
coated with the "slag" created during destruction of a needle. Thus, current
will either not flow or flow only intermittently from the electrodes into the
needle, thereby leaving all or parts of the needle intact.
Moreover, even if the needle is adequately destroyed~ there
may be some residue of material from the needle or the syringe left inside the
destruction device. Thus, U.S. Patent No. 4,961,541 to Hashimoto indicates
that "a disinfectant may be sprayed onto the syringe during the collapsing
operation." However, spraying each syringe is time consuming and easily
forgotten in the press of other duties. Also, there is no provision for
elimin~tin~ airborne emissions during destruction of the needle. Without
proper precautions and/or a sufficiently fast destruction process, airborne
pathogens may leave the hollow needle before, during or after the destruction
process.
Additionally, for each of the above-described devices, the user
appalelltly must carry the needle to the device for destruction. This activity
increases the risk that medical personnel or others inadvertently may prick
themselves with a needle before it is destroyed. U.S. Patent No. 5,046,669 to
Wallace, et al. recognizes that collecting used hypodermic needles for
destruction entails significant problems. Wallace, et al. thus provides a
collection unit and a centrally located processing unit that both breaks the
needle into fragments and melts the plastic syringe housing.
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It would also, however, be desirable to have a cornpact,
portable device that can, for in.ct~nce, be moved to locations where blood is
being taken or vaccinations given, remote from health care facilities or that
can be transported within a larger medical facility by a nurse or orderly
m~king rounds. Other than the "self-powered" Spinello device that only
increment~lly destroys needles and does not appear to foreclose airborne
emissions, no truly portable, compact and inexpensive destruction devices
are available, however. Tn~te~l, many of the destruction devices are outfitted
with numerous "bells and whistles," such as bulky transformers for coupling
the device to a main power supply or infrared sensors for activating the
device, that add complexity and cost. Such complexity is entirely
unnecessary for many users, who simply desire to completely destroy their
needles before disposal. Exemplary of such users are diabetics and dentists,
both of which groups make use of very small and fine needles. While these
persons desire to dispose of used needles properly, the high cost of the overly
complex destruction devices dissuades such proper disposal.
SUMMARY OF THE INVENTION
The present invention addresses the above problems by
providing a portable device that can be used in a variety of locations~ may
have a self-contained power source, fully destroys needles of various lengths
and gauges in one step, and sterilizes and/or prevents escape of pathogens
and potential cont~minslntC Additionally, one embodiment of the present
invention provides a simple and inexpensive needle destruction device that is
capable of destroying instantly and completely small needles such as those
used by dentists or diabetics.
Briefly, the present invention is a portable needle destroying
device provided with a power supply such as a replaceable or rechargeable
battery, an adjustable dial that is used to set the gap between two electrodes
J 30 in order to allow needles of varying gauge to be used with the device, and a
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filter infused with disinfectant that prevents particulate or airborne pathogensfrom escaping from the device. The battery may be rechargeable. Instead~
however, of connecting directly to one of the electrodes, the battery may
couple to an energy storing device such as an inductor, capacitor or thyristor
S circuit. The storage device is charged by the battery and holds a charge for
release when a needle is inserted and creates a short circuit across the gap
between the electrodes. The released charge, or arc, is powerful enough to
destroy small needles completely without requiring the user to insert
successively smaller lengths of the needle into the device in order to ensure
10 the needle's destruction. Alternatively, even for large needles, the releasedcharge significantly speeds the destruction of the needle and the battery may
also supply power to the electrodes so that complete destruction of larger
needles is quickly completed following initial insertion and release of the
stored charge.
The device accommodates needles of all lengths and gauges
by providing a means for adjusting the gap between the electrodes. The
adjusting means is controlled by a dial that the user turns to move an
adjustable electrode. Turning the dial in one direction decreases the bias of a
spring to allow the adjustable electrode to move away from a second
20 electrode and thereby more efficiently accept a larger needle. Turning the
dial in the other direction increases the spring bias and forces the adjustable
and second electrodes closer together to accept a smaller needle. Absent
such adjustment it is exceetlingly difficult for the user completely to destroy
all of the needle. If the gap were too large for a small needle, likely the user25 would be forced to rock the needle back and forth to ensure complete contact
between the needle and electrodes. Such rocking possibly would be
insufficient and leave a dangerous, sharp "nub" of needle. Alternatively, if
the gap were too small, use of larger needles would more quickly wear down
the electrodes, ultimately possibly causing electrode failure or at least
30 leading to replacement of the electrode sooner than otherwise necessary.
--4--
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In one embodiment, the power supply may couple to a motor
that optionally rotates the second electrode in order to remove the slag
produced during destruction of the needle, as is generally shown and
described in U.S. Patent No. 5,138,124 to Kirk, et al., which is hereby
5 incorporated in its entirety by this reference. When the power supply is a
battery, a direct current ("dc") motor should be used. Because the motor may
be ~ctll~tl~d when the user slides a needle into the device and thereby
electrically connects the adjustable and second electrodes and causes release
of the stored charge, a high starting torque motor (like a dc motor) may be
10 used in order to begin immediately rotating the second electrode. Immediate
rotation ensures that the "slag" or other residue produced by the destruction
of the needle is thrown into a disposable cartridge by the rotation o:f the
second electrode rather than attaching to, and decreasing the effectiveness of,
the electrodes.
In an alternative embodiment, the second electrode is a flat
plate with at least one slanted edge. A moving or vibrating means couples to
- the plate for reciprocating the plate back and forth, thus causing the slag toflow down the sides of the plate and effectively cleansing the electrode. The
movement or vibration need not result in great displacement of the electrode.
20 although vibrating the electrode at a high frequency, and beveling one edge
of the electrode, may assist in dislodging subst~ntiz~lly all of the slag. One
such vibrating means may be a buzzer circuit, which utilizes a coil to
produce a magnetic field that pulls a metallic strip toward the coil. When the
strip is moved away from its resting plate, a short is created between the coil
25 and its power supply, resulting in the strip returning to its resting place, at
which point the circuit is energized and the strip is again pulled from its
resting place. (The frequency of the buzzer circuit can be adjusted by
ch~ngin~ the amount of field produced by the coil or the spring
characteristics of the strip). By coupling one end of the strip to an electrode
30 the electrode will reciprocate back and forth as the strip is moved back and
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forth. Another moving means may simply be a motor whose shaft rotates
and eccentric weight, which causes the motor to vibrate. Mechanically
coupling the motor to the electrode translates the vibration into the electrode.
While the motor may be used to move the electrode, its shaft
may also couple to a fan that pulls smoke, dust or particle-laden air through a
case holding the battery, motor, electrodes and a disposable cartridge. The
air is channelled through the disposable cartridge, which is sealed via a
gasket to the side of the case in order to prevent smoke, dust or particles fromentering the case that surrounds the motor. The air travels through a filter
that is impregnated with a disinfectant and loaded into a removable tray to
allow replacement of the filter or replenishment of the disinfectant. The
disinfectant both cleanses cont~min~tes from the air and deodorizes the
emissions caused by vaporization of the residues left in the needle. A timer
on a control board that couples to the motor ensures the motor operates for a
predetermined interval so that the fan will pull sufficient air into the cartridge
to prevent any of the vapors and fumes generated from the destruction of the
needle from escaping unfiltered and unfreshened via the impregnated filter.
In another embodiment, the device comprises a case that
encloses a battery that may be coupled to an energy storing circuit, a first
electrode and a second electrode. Either of the first or the second electrodes
may be provided with the adjusting means adjustor that allows the user to
adjust the gap between the first and second electrodes in order to size the
gaps for accepting needles of different sizes. The energy storing device may
comprise a capacitor, inductor or a thyristor circuit that may couple to the
battery, store a charge, and instantly release the stored charge when a needle
is inserted through a hole in the case and contacts both electrodes. If the
needle is small enough, the released charge normally destroys the entire
metallic tip of the needle virtually instantaneously. This embodiment is thus
particularly useful for destroying "double-ended" needles that have a first
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needle portion with a sharpened tip extencling outside the syringe body and a
second needle portion that extends through a hub and into the body of the
syringe. Normally, because the second portion of the needle is surrounded
by the syringe, destruction of the needle requires an inconvenient, two-step
S process, whereby the user first destroys the sharpened, first portion of the
needle, then removes the hub and destroys the second portion of the needle
that extends into the syringe body. Utilizing the energy storing device,
however, allows the present invention to generate a sufficiently powerful arc
and discharge that the entire length of the needle (e.g., both the first and
10 second portions) is destroyed upon insertion of the needle into the h,ole for contacting the two electrodes.
A recharge pack can be provided for use with the battery.
LEDs may be used to indicate whether the battery needs a recharge or when
the capacitor will be recharged and ready to destroy another needle.
In short, the present invention provides a device for safely and
efficiently destroying completely a hypodermic needle of virtually any size
and preventing the escape of vapor, dust, particles or air-borné emissions
upon destruction of the used needle. Apparatus for removing slag from the
electrodes is provided, thereby maximi7ing the performance of the
20 electrodes. A portable, inexpensive version of the invention can be used to
destroy completely small needles, including double-ended needles.
It is accordingly an object of the present invention to provide
a portable device for destroying needles.
It is another object of the present invention to couple a power
25 supply to an energy storage device that provides a discharge sufficiently
powerful to at least partially destroy a used needle.
It is a further object of the present invention to provide a dial
coupled to a gap adjustor for properly sizing the gap between electrodes that
convey electric currents to the needle to be destroyed.
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It is an additional object of the present invention to provide a
filter impregnated with disinfectant for thoroughly cleansing vapors and
other cont~min~tes released upon destruction of a used needle.
Other objects, features and advantages of this invention will
S become ~ llt with reference to the rem~in~1er of this docurnent.
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BR~EF DESCR~PTIO N OF THE DR~ WIN GS
FIG. 1 is a schem~ic diagram of the components of one
embodiment of the present invention.
FIG. 2A is a side view of one embodiment of the present
invention provided with an adjustable and a rotating electrode with the
adjustable electrode set for accepting a small needle.
FIG. 2B is a side view of the embodiment shown in FIG. 2B
with the adjustable electrode set for accepting a large needle.
FIG. 3 is another embodiment of the present invention
provided with an adjustable electrode and a vibrating electrode plate.
FIG. 4 is a schematic diagram of the components of a port~ble
and inexpensive embodiment of the present invention provided witih a
storage circuit for supplying a large, almost instantaneous discharge to
destroy small needles.
DETAILED DESCRIPTION OF THE DR~WINGS
FIG. 1 shows in a schematic block diagram one embodiment
of the portable needle destruction device 10 of the present invention. A case
11 encloses a power supply such as a battery 12 that couples to a control
board 14 that includes a timer 15. A recharging outlet 16 may be provided to
allow the device 10 to be plugged into a recharging device in order to
replenish the battery 12. Power lines 18 lead from the control board 14 to a
charge or energy storage circuit 20 and then to a motor 22. Storage circuit 20
typically consists of a capacitor, although other devices such as an inductor
or a thyristor circuit may also be used. LEDs 13 may also be provided on the
outside of the case to indicate to the user whether the battery 12 needs to be
recharged or whether the storage circuit 20 has recharged and the device 10
is thus ready to accept and destroy another needle.
Motor 22 drives a motor shaft 24 that rotates a first pulley
wheel 26 and a paddle-wheel fan 32 that has a number of slats 34. An o-ring
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belt 30 couples the first pulley wheel 26 to a second pulley wheel 28, which
in turn drives an electrode shaft 40. Forming the first and second pulley
wheels 26 and 28 from a plastics material, such as phenolic, and using an o-
ring belt 30 ensures that if a user jams a needle 70 into the device 10, the
pulley wheels 26 and 28 will stop while the motor 22 overload initiates.
At the end of the electrode shaft 40 is a rotating electrode 44.
Power is transferred to the rotating electrode 44 via brush 42 that couple the
power lines 18 to the conductive electrode shaft 40. Although the brush 42
could abut the end of the electrode shaft 40, placing the brush 42 on the side
of the electrode shaft 40 ensures better power transfer. Alternatively, the
brush 42 could couple directly to the rotating electrode 44, with a channel
separating the brush 42 from the end of the rotating electrode 44 to prevent
needle residue from interfering with the power transfer accomplished by the
brush 42.
An adjustable electrode 46 is separated from the rotating
electrode 44 by a gap 52, as can perhaps best be seen in FIGS. 2A and 2B. A
gap adjusting means 54 allows the user to turn a dial 56 and adjust the gap 52
between the rotating electrode 44 and the adjustable electrode 46, which is
biased by a spring 60 to bear against a fulcrum 62. A spring-loaded set
screw 64 is used to set the initial size of the gap 52. Rotating the dial 56
causes it to go up or down a threaded screw 58; the end 57 of the dial 56 thus
is moved toward or away from the adjustable electrode 46. Because the
spring 60 biases the other end of the adjustable electrode 46 upwards,
moving the dial 56 moves the end 57 up or down, causing the adjustable
electrode 46 to pivot toward nor away from the rotating electrode 44.
Alternatively, if the geometry of the case 11 does not allow placement of the
dial 56 directly over the adjustable electrode 46, a second length of material
could connect between the end 57 of the dial 56 and the adjustable electrode
46 in order to transfer the force generated by turning the dial 56 into motion
of the adjustable electrode 46.
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Adjustable electrode 46 defines a bevel 48 that ends in a tip
50 for concentrating eleckic potential and delivering the current into a
metallic needle tip 71 once the needle tip 71 is inserted through an opening
68 in the case 11 and contacts both the adjustable and rotating electrodes 46
S and 44. A guide 74 is provided that may be generally funnel shaped and
spring-loaded with a spring wrapped around flexible portions that open
farther depending on the size of the needle 70 being inserted into the opening
68. Guide 74 ensures that the needle tip 71 is brought directly to the gap 52
for destruction. Thus, the guide 74 elimin~tes the need to "rock" back and
10 forth the needle tip 71 do in order to achieve contact between the needle tip 71 and the electrodes. Guide 74 also hides sparks created during the
destruction process from the user and decreases the possibility that waste
created during destruction will be thrown through the opening 68 and
possibly onto the user's hands.
Contact ofthe needle tip 71 with the electrodes essentially
closes an open circuit consisting of the electrodes in parallel with the storagecircuit 20 and the battery 12. Closing the circuit causes the storage circuit 20immediately to discharge and create an arc across the electrodes that destroys
the needle tip 71. About six (6) volts from the battery 12 has been found
20 sufficient to deskoy most needles 70, particularly since the storage circuit 20
initially greatly multiplies the effective current transfer through the
electrodes into the needle 70.
Delivery of current into the needle tip 71, which has a high
electrical resistance, heats and melts the needle tip 71 into the slag 72.
25 Rotation of the rotating electrode 44 throws the slag 72 down into a cartridge
80 and also "pulls" the needle tip 71 further into the device 10. Use of a
shield, located inside the case 11, to surround the rotating and adjuslable
electrodes 44, 46 may further ensure that the slag 72 is directed down into
the cartridge 80 and does not escape back through the opening 68. Although
30 much of the residue left in the needle tip 71 after use will be destroyed by the
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current, some smoke. vapor or dust will be generated. Guide 74 and a shield
may prevent much of this material from escaping back out of the opening 68;
however, absent operation of the fan 32 much of this material will escape.
Fan 32 pulls air through the opening 68 and into the cartridge
80. The air is laden with the emissions from the destruction of the needle tip
71 and is channeled into a filter 82, which is impregn~te~l with a strong
disinfectant both to sterilize any pathogens that may have been in the needle
tip 71 and not destroyed, and to freshen the air. Filter 82 may be formed of
multiple membranes that better trap particles of varying sizes. In order to
allow replenishment of the disinfectant or replacement of the filter 82, it is
held in a removable tray that can easily be inserted in and removed from the
case 11. Alternatively, a door or sliding access hatch could also be used to
gain access to the tray holding the filter 82. After passing through the filter
82, the now deodorized air exits the case 11 through exhaust vents 84. A
gasket 86 prevents unfiltered air from passing through the cartridge since
allowing unfiltered air through not only results in odorous emissions from
the case 11 but also may result in the motor 22 being clogged by the particles
found in the unfiltered air.
FIG. 3 shows an embodiment of the present invention
provided with a case 100 enclosing another adjusting means 102 for
adjusting the distance between a movable electrode 110 and a conductive
plate 120. Case 100 also surrounds and contains a power supply, which may
- be either a battery 12 or a transformer that may couple to a main power
supply via a conventional plug and cord, a storage circuit 20 and a motor
130. (Optionally, the filtration system, comprising a fan and a filtered
cartridge may also be placed within the case 100).
Movement or vibration of the vibrating plate 120 ensures that
slag 72 does not build up upon the surfaces of the vibrating plate 120 that
acts as an electrode for conducting current to a needle tip inserted through a
hole 101 in the case 100.for destruction. Vibration can be accomplished by
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U~ D~G 199~
mounting the high rpm motor 130 to the vibrating plate 120. Placing an
eccentric weight 132 on the motor shaft causes the motor to vibrate and the
vibration is mechanically transmitted to the vibrating plate 120. Vibr~tion
also may be accomplished by spring-loading vibrating plate 120, attaching a
5 cam to a rotating shaft driven by the motor 130 and abutting a cam against
one end of the plate 120. Rotation of the cam will translate into mecharlical
vibration of the spring-loaded vibrating plate 120.
Alte.rn~tively, vibrating plate 120 could be con~tr~ine(l in a
channel or track and have one end coupled to a vibrating means that will
10 reciprocate the vibrating plate 120 back and forth within the track in o:rder to
remove slag that may otherwise attach to the vibrating plate 120. One such
reciprocating means may be a bll7.7er circuit, although any means for rnoving
the vibra~ing plate 120 may also be used. Additionally, a-cleaning
mech~ni~m may be provided for allowing the user to clean the vibrating plate
- 15 120 off. The cleaning m~ch~ni~m may be a blade located adjacent t~ the-
track and capable of being moved, ylere~dbly by the us~r, close to the track
in order to "wipe" the vibrating plate 120 free of slag or other residue after
~ destruction of one or more needle(s). ~ ;vely, the clea~ng mech~nism
may simply be an adjustable block, o~e surface of which IS a cleaning
surface that may be brought into contact with the vibrating plate 120 and
either be m~ml~lly moved across the surface of the vibrating plate 120 or
held against its surface during vibration or movem~l,l of the vibrating plate
120. - -
'- . A set screw 105 can be used to set the initial gap between the
movable electrode 110 and the vibrating plate 120, which may be shaped in
the form of a triangle with one of the legs abutted against and loosely
attached to the case 100. The gap 50 can be wi:dened or l~ w~;d by - -
manipulati~ e adjusting means 102 to reorient the movable electrode 110
~ from a position suitable for destroying a small gauge needle (whose diameter
is Dsg), indicated by Psg, to a position suited for destroying a large ga.uge
.
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AMENDE0 SI~EEl
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needle (whose diameter is Dlg), indicated by position Plg. Adjusting means
~ 102 may operate by having a user turn a dial 103 to select a needle size.
Turning the dial 103, which may be loaded with spring 104, forces the end of
a set screw 105 down against the back of the movable electrode 110. The
S force apphed by the set screw lOS overcomes the bias spring 106, c~ ing
the movable electrode 110 to pivot about pivot point 108.
The initial position of the movable electrode 110 is partially
~let~.rmined by the amount of vertical displacement vibration causes in. plate
120. In order to ensure that the plate 120 does not inad~elLelllly touch~ -
movable electrode 110 during vibration, it may be n~cçss~ry to vibrate the
plate orlly along its horizontal àxis. A lead may be secured to the vibrating
plate 120 and the movable electrode l lO for conveying current to the
electrode 110 and plate 120. Insertion of a needle into the hole 101 causes
- destruetion of the needle tip. ~es-llting slag 72 or other debris.is shaken
~ 15 firom the plate 120 via vibration and f~lls into the cartridge 8Q that may be .
provided with the disillfe~ impregn~te~l filter 82. - . =--
~ ~ An additional embodiment is shown in ~I(i. 4. -.This. simple,
portable device 140 is provided with a batte~y 12, coupied to a c~p~citQr 142
- . and power lines 18 that lead to first and sec.ond electrodes 144, 146. Note
that the first and second electrodes 144, 146 -may b~ fixed QF:-~e~.ond
electrode 146 may be coupled to a slag removing means.l48 that, possibly
through operation of the motor 150 on comm~n-l of t .he control. board 14,
moves the second electrode 146 to cause slag to fall off of the second
electrode and into the cartridge 80. However, the slag removing means 148
is ~otally optional for this embodiment since it is ~lecign~cl for very small
needles that the capacitor 142 generally will be alone sufficient substa~tially
to destroy.
The foregoing is provided for purposes of illustrating,
explaining and describing several embo-liment~ of the present invention.
Modifications and adaptations to these embo~liment~ will be a~a~ ll to
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AMENl~D SH~
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those of ol-lhlal y skill in the art and may be made without departing from the
scope or spirit of the invention and the following claims.
